Air-free liquid variable light filter system

ABSTRACT

A hermetically sealed, air-free system for screening and filtering electromagnetic ray energy from the sun, having a means within the system for changing from one degree of screening and filtering to another by the use of two or more immiscible liquids in a light transmission cavity, said liquids having different specific gravities so as to maintain separate liquid bodies while stationary within the system and while being changed.

U1-u3-73 GR 357245929 0 Umted States Patent 119-1 1111 3,724,929 Lacy 151 Apr. 3, 1973 541 AIR-FREE LIQUID VARIABLE LIGHT 2,439,553 4/1948 Winn.350 312 x FILTER SYSTEM 2,489,751 11/1949 Candler ....350/312 x2,596,566 5/1952 Lacy et al ..350/312 [75] Inventor: Mount L. Lacy,Jacksonville, Fla. 2,783,682 3/1957 swensonw "HMO/312 x 3 016 801 1/1962Michel ..350/312 [73] Ass1gnee: Mount Lacey Enterprises, Inc., Salt L ey, Ut 3,368,862 2/1968 Dean ..350/312 [22] Filed: Jan, 12, 1971 PrimaryExaminer-David Schonberg Assistant Examiner-Ronald J. Stem [21] Appl'105,985 Attorney-Stevens, Davis, Miller & Mosher Related U.S.Application Data ABSTRACT [63] Commune of Apnl A hermetically sealed,air-free system for screening abandoned.

and filtering electromagnetlc ray energy from the sun, having a meanswithin the system for changing from [52] U.S. Cl ..350/312G, 137/563 onedegree of screening and filtering to another by the [5 I I I v u u I a eu v a I 1 n u a u u e u a e v a a u a [58] Field Of Search....,..350/3l2, 314, 276, 267; mission i y i iq d having different specific303/104; 137/558 583 ravities so as to maintain se arate li uid bodieswhile g P q stationary within the system and while being changed. [56]References Cited 7 23 Claims, 9 Drawing Figures UNITED STATES PATENTS786,613 4/1905 Villani ..350/312 P mnEnma m5 3,724,929

SHEET 2 OF 3 INVENTCR MOUNT L. LACY BY M MJW ORNEYS AIR-FREE LIQUIDVARIABLE LIGHT FILTER SYSTEM This is a continuation application ofapplication Ser. No. 628,984 filed Apr. 6, 1967, now abandoned.

This invention relates to a device that will screen and filter rays fromthe sun and that can change from one degree of screening and filteringto another to effect controlled transmission of solar radiation.

Many attempts have been made to provide windows, roofs, and skylightswith devices having means between sheets or plates of transparentmaterial that would remove harmful or undesirable electromagneticradiation from the sun, such as infrared rays, and the like. Thesedevices employ a cavity or a series of cavities defined by spacedtransparent plates and contain within the cavity liquid capable ofscreening or filtering the undesirable or unwanted radiation from thesun passing through the liquid in the cavity. One of the principaldifficulties in using such devices is the requirement for changing fromone liquid to another in order to change the type of filtering of thesun's rays to make such a system practical. Heretofore, the systems havenot been air-free and thus the problem of air bubbles occurred bringingabout interphase mixing of the liquids. To eliminate the interphaseproblems between liquids, some prior art systems utilized double cavityarrangements having a different liquid in each cavity. This type ofsystem is bulky and expensive to build, operate, and maintain.

This invention presents a device that overcomes the difficulties of theprior art devices and contemplates an hermetically sealed, substantiallyair-free screening and filtering system for radiation from the sun byproviding two equally spaced sheets or plates of transparent materialwith a gasket between them positioned around their outer edge so as toform a thin, elongated cavity therebetween. Suitable entry and exitconnections are provided at the top and bottom of the cavity to allowfor flow of liquids contained in the cavity through the openings to andfrom a reservoir tank connected to said openings. When the systemcontains two immiscible liquids, one heavier than the other, one liquidflows from the reservoir through one opening into the cavity while theother liquid flows from the cavity through the other opening to areservoir tank. Since each of the immiscible liquids has a differentspecific gravity, one will gravitationally position itself below theother and present a clearly delineated interphase between the liquids.Each liquid will have different capabilities for screening or filteringthe rays so that, depending on which liquid is in the cavity, there maybe no filtering when a light liquid is used, or there may be varyingdegrees or different types of filtering accomplished when a heavy liquidis used.

The system of this invention is hermetically sealed by having a bleedervalve arrangement so that air can be excluded from the system to reduceto a minimum the formation of air bubbles within the system when theliquids are being interchanged to effect different types of screeningand filtering. When the heavy liquid is in the cavity, the lighterliquid is mainly in the reservoir. To change from the heavy liquid tothe lighter one, a pumping means conveys the heavy liquid from thecavity through an opening or openings in the bottom of the cavity intothe reservoir tank which forces the lighter liquid through the openingor openings in the top of the cavity, thus maintaining a closed,air-free system with an interphase movement in both the cavity and thereservoir tank as the change of heavy liquid for a light one is made.

Advantageously, the screening and filtering system of this invention maybe arranged so that the reservoir tank has an expansion means in it toaccommodate for expansion and contraction of the liquids due to heatingof the liquid or changes in cavity size due to heat or wind pressure.such an expansion means allows for the maintenance of an air-free liquidsystem which can operate without the introduction of air bubbles thatwould make the system both unattractive and inefficient.

Advantageously, the elongated, relatively thin cavity of this inventionmay be somewhat curved or convex in form by using two mating, equallyspaced, convex or curved transparent plates with a gasket around theiredge to maintain them at an equal distance from each other, and thusform a rigid structural member that is capable of providing a relativelylarge transparent area, such as for windows, domes, and the like. Thecurved arrangement of the transparent sheets provides for strength ofthe cavity unit and maintains the space between the sheets constant overa large service area, such as is required when this system is used toscreen and filter unwanted radiation from car tops, airplane canopies,windows, large dome arrangements, and the like. It has been found in thecase of windows that, by being made convex, they will withstand windageto 1,000 m.p.h., which is a safety factor of 600 percent. Also, thespace between the transparent sheets may be from about. one-sixteenthinch to about three-sixteenths inch depending on the type of liquids tobe used, their viscosity, and the thickness of screening and filteringliquid for the type of filtering to be done.

Advantageously, the system of this invention may employ three or moreimmiscible liquids, each heavier than the other, so that a multiple ofscreening and filtering effects can be had. For example, one liquid canbe provided for normal light transmission through the device, anotherliquid can be used for removing infrared rays, and still another mayadmit the infrared while blocking some of the rays in the visible range,and so forth. Such a system can provide for screening out visible rayswhile admitting solar heat radiation to supplement heating systems inthe winter, or can screen out the infrared rays to assist coolingsystems in the summer. Thus it can be seen that the device of thisinvention can provide a variety of screening and filtering effects in aunitary, uncomplicated system that requires only the flip of a switch tochange the screening and filtering capacity of the cavity in the device.

It has been found that the liquids employed in this invention must beimmiscible to each other and have good surface wetting properties forglass, Lucite, or other types of transparent material. The liquids alsomust have good cleaning action that leaves no residue and should havesubstantially the same viscosity. If infrared rays are to be screenedout, glycol (antifreeze) may be used for the heavy liquid, and whenlight is to be admitted substantially unfiltered, white mineral oils(light oil) may be used. Exemplary of these light oils are thePenn-Drake white mineral oils known as Drakeol 6." Their Drakeol 7" and9 and Clearteck," Liteteck," and "Peneteck" also may be used. ThesePennDrake oils are produced by the Pennsylvania Refining Company and theproperties of the oils are disclosed in their bulletin entitled ProductSpecifications Penn-Drake White Mineral Oils." It will be appreciatedthat the heavy liquid may contain various colors in solution or a truesuspension capable of filtering different types of solar radiation, andthat density of the color in the liquid may be such as to efi'ect therequired degree of filtering in relation to the cavity.

The screening and filtering system of this invention may be used inwindows, automobile tops, airplane canopies, space helmets, eyeglasses,Windshields, partitions, roof tops, homes, astrodomes, signs, and thelike. It has been estimated that when used as windows in commercialbuildings, a 25 percent saving on heating can be achieved and a 50percent saving in air conditioning installation and operating cost. Thewindows of this invention also eliminate the need for awnings, venetianblinds, sun drapes, sun screens, and the like.

These and other objects of my invention will become apparent from thedescription of the following embodiments and the drawings thereof inwhich:

FIG. 1 is a view in elevation of an automobile showing my screening andfiltering device positioned in the top of it;

FIG. 2 is a plan view of the automobile showing the screening andfiltering device;

FIG. 3 is a view taken on the line 3-3 of FIG. 2 showing the means forconnecting the device to the roof of the automobile and the curvedtransparent plates spaced by a gasket to provide the thin, elongatedcavity;

FIG. 4 is the schematic arrangement of the device illustrated in FIG. 1,showing a reservoir tank for holding two immiscible liquids and a pumpfor conveying the liquids between the reservoir and the cavity;

FIG. 5 is a cross-sectional view taken on line 5--5 of FIG. 4 showingtwo immiscible liquids in the reservoir and a liquid expansion ballmeans operatively connected to it;

FIG. 6 is a fragmentary view of a portion of the reservoir as shown inFIG. 5 with a diaphragm type liquid expansion means operativelyconnected to it;

FIG. 7 is a fragmentary view, partly in cross-section, taken on a line77 of FIG. 4 showing a typical inletoutlet connection to the cavitybetween plates'for the entrance and egress of liquid during the changingof liquids;

FIG. 8 is a view in elevation of a window employing the system of thisinvention; and

lar gasket 24 by a U-shaped channel 26 which clips over the edges of theplates to hold them tightly in sealed arrangement against tubular gasket24. The bottom of the U-shaped channel 26 has a rubber molding 28against it and the whole edge assembly of the plates is positionedwithin a second U-shaped channel 30 which has an extension 32 from itsupper leg which extends over the roof 12 of the automobile so as toposition the assembly in the roof. The roof of the automobile defines anopening 34 into which fits an L-shaped channel 36 against which thebottom of U-shaped channel 30 abuts with the rubber molding 28 fittedagainst the bottom of the U-shaped channel 30. Two tubular gaskets 38,40rest between the inner ends of the U-shaped channel 30 and the outersurfaces of the plates 18,20 respectively to form a tight encasement ofthe transparent roof section 14 in the roof of the automobile. A rubbergasket 42 is positioned under the horizontal leg of the L-shaped channelwhich in turn abuts against the inner surface of extension 32 of U-shaped channel 30 (see FIGS. 1, 2, and 3).

The transparent roof section 14 has low point of gravity openings 50,52and a high point of gravity opening 54 which communicate with the cavity22. The openings are all formed by drilling a hole through one of theplates 18,20 and cementing to the plate a conduit connector 56 overwhich the end of a conduit 58 is placed. Opening 54 has conduit 58connecting the top of reservoir 60 with the high point of gravity ofcavity 22. In like manner, low point of gravity openings 50,52

FIG. 9 is a crosssectional view taken on a line 9-9 H of FIG. 8 showingthe device connected to a window joist.

In the drawings, numeral 10 illustrates a standard automobile having aroof 12. Mounted in the roof of the automobile is transparent roofsection 14 held to the roof by a series of spaced bolts 16. Thetransparent roof section is formed from two curved sheets or plates 18,20 of transparent plastic, such as Lucite," equally spaced from eachother to form a cavity 22 therebetween. The plates 18,20 are held inspaced relation to each other by a tubular gasket 24 which is positionedaround the edge of each plate to complete the cavity 22. The plates areheld together against the tubuhave conduits 62,64 which connect the lowpoint of gravity of the reservoir with the cavity 22 through conduit 66.In conduit 66 is positioned a pump 68 for pumping the heavy or highspecific gravity liquid into and out of the cavity. The pump iscontrolled by a solenoid switching means 70. Also, a second solenoidswitching means 71 may be used. A filter 72 is positioned in line 66 toremove any foreign material that may be in the liquid or be developedduring the'operation of the system. On top of reservoir 60 is positioneda bleeder valve 74 to remove air from the system and put liquids intoit. Connected to the reservoir 60 is an expansion means 76. Theexpansion means has a rubber ball 78 surrounded by coarse wire mesh anda conduit pipe 82 for passing liquid to and from the ball. When theliquid in the system expands, the rubber protrudes out of the spacesbetween the wire mesh, thereby providing the volume for taking up theexpansion (see FIGS. 4, 5, and 7).

In FIG. 6 is shown an alternate arrangement for providing for expansionof the liquid in the reservoir designated as 60'. On the side of thereservoir 60' is positioned a diaphragm 86 having a rubber diaphragmplate 88 over a hole 90 defined by the reservoir 60. When the liquidexpands, the diaphragm plate 88 bulges outward, thereby providing thevolume for expansion of the liquids in the system (see FIG. 6).

It will be appreciated that the light screening and filtering system ofthis invention heretofore described has many types of use. In FIGS. 8and 9, there is shown its application to a transparent window sectionwhere the light liquid enters the cavity 22 between plates l8',20'through a high point of gravity opening, and the heavy liquid enters thelow point of gravity opening in cavity 22. The transparent windowsection has a U- shaped channel 26' which holds the plates l8',20'against a tubular gasket 24' with a rubber molding 28' resting againstthe bottom of the U-shaped channel 26' and a U-shaped section 30 whichhas a leg extension 32- that is held by screws 16 against window frame102 with a rubber gasket 42' therebetween.

In operation, equal amounts of two immiscible liquids of differentspecific gravities are placed in the reservoir 60 until the cavity 22and the conduits, filter, and pump are all filled so that there is noair in the system. The system is closed by a bleeder valve whicheliminates the air in the system and provides for hermetic sealing ofthe system. The pump means 68 is then set in motion by solenoidswitching means 70 to bring one liquid (the one desired) into thecavity, the other liquid being in the reservoir 60. The pump operates soas to pump the heavy liquid in or out of the cavity. When it is pumpingthe heavy liquid out of the cavity, it is forcing the light liquid intothe high point of gravity opening and thus presenting a cycling of theliquid when the interphase between them moving in the direction ofpumping. That is, if the heavy liquid is being pumped out, theinterphase in the cavity is receding to the low point of gravity whilethe interphase in the reservoir is rising to the high point of gravity,and vice versa. Any foreign material that develops during the operationof the system is removed by filter 72.

It will be appreciated that the light screening and filtering system ofthis invention may be operated to present more than two different typesof liquid by increasing the size of the reservoir to hold them.

Also, more than one reservoir may be used with a common liquid in thecavity, which makes up one of the immiscible liquids, and otherimmiscible liquids in the system that have different characteristics forscreening and filtering solar energy. In this type of system, a solenoidfor each reservoir is provided so that, after the common liquid fillsthe cavity, a second solenoid would be activated which would cut off thereservoir that had been operating and would pump different liquid fromanother reservoir to replace the common liquid which would then enterthe reservoir being operated. This procedure could be used on aselective basis with the several types of liquids contained in severalreservoirs, thus providing a plurality of different liquids forselective pumping into the cavity to obtain the particular screening andfiltering desired among those available from the different liquids inthe reservoirs.

Various modifications of the specific embodiments described and shownmay be made, and it is understood that the specific embodiments are byway of illustration of the invention and not limiting thereof.

What is claimed is:

1. An hermetically sealed air-free light energy screening and filteringdevice comprising transparent plates defining a closed cavitytherebetween; a reservoir; a conduit connecting said reservoir andcavity at high gravity points; a conduit connecting said reservoir andcavity at low gravity points, said cavity, reservoir and conduits beingfilled with at least two bodies of immiscible liquids having differentlight filtering properties and having at least two separate interphasesbetween them within said device, said device being completely free ofair; and a reversible pump acting on only one of said liquids directlyfor moving both said liquids as a unit to and from the cavity and to andfrom the reservoir to effect change in the body of liquid in saidcavity.

2. The light energy screening and filtering device of claim 1 in whichsaid pump is in the low gravity point connection between said cavity andsaid reservoir.

3. The light energy screening and filtering device of claim 1 in whichsaid pump is in the high gravity point connection between said cavityand said reservoir.

4. The light energy screening and filtering device of claim 1 in which afilter is positioned in at least one of the connections between saidcavity and reservoir to clean said liquids.

5. The light energy screening and filtering device of claim 1 in which ableeder valve is positioned in the system to eliminate air within theliquids.

6. The light energy screening and filtering device of claim 1 in whichsaid reservoir has an expansion means for accommodating expansion andcontraction of said liquids.

7. The light energy screening and filtering device of claim 6 in whichsaid expansion means is a diaphragm in the side of said reservoir.

8. The light energy screening and filtering device of claim 6 in whichsaid expansion means is a rubber ball covered with coarse mesh wire.

9. The light energy screening and filtering device of claim 1 in whichsaid immiscible liquids are oils of different specific gravities.

10. The light energy screening and filtering device of claim 1 in whichsaid immiscible liquids are of different colors.

1 l. The light energy screening and filtering device of claim 1 in whichone oil is a light mineral oil and the other is a heavy glycol.

12. The light energy screening and filtering device of claim 1 in whichtwo interphases are between the liquids in the system, one interphaserising as the other interphase descends as one liquid replaces the otherin said cavity.

13. The light energy screening and filtering device of claim 1 in whichsaid cavity is defined by two transparent curved plates spaced apart bya tubular gasket around the edge of the two plates.

14. The light energy screening and filtering device of claim 13 in whichthe plates are plastic.

15. The light energy screening and filtering device of claim 13 in whichthe plates are glass.

16. The light energy screening and filtering device of claim 1 in whicha plurality of reservoirs is used each having a pump controlling it anda different liquid in each reservoir for providing a different filteringand screening effect to serve as one of the liquids in the system, and acommon liquid for the other liquid in the system, whereby the operationof any one pump when the common liquid is in the cavity causes theparticular liquid in the operated reservoir to fill the cavity.

17. The light energy screening and filtering device of claim 1 in whichsaid transparent plates are positioned horizontally.

18. An hermetically sealed air-free device for screening and filteringlight radiation comprising two spaced transparent plates having a gasketbetween them and positioned near their edges to define a sealed cavitytherebetween; openings through one of said plates at the upper and lowergravity points of said cavity; a reservoir having upper and lowergravity point openings; a first conduit connecting the upper gravitypoint opening in said reservoir with the upper gravity point opening insaid cavity and a second conduit connecting the lower gravity pointopening in said reservoir with the lower gravity point opening in saidcavity; two immiscible liquids of different specific gravities and ofdifferent light filtering properties completely filling said device andhaving at least two separate interphases between them within saiddevice, said device being completely free of air; and a reversible pumppositioned in said second conduit for pumping only the liquid of higherspecific gravity to effect a movement of both liquids in or out of saidcavity and in or out of said reservoir.

19. The light energy screening and filtering device of claim 1 in whichsaid transparent plates form a substantial portion of an automobileroof.

20. The light energy screening and filtering device of claim 1 in whichsaid transparent plates form a window in a building structure.

21. The light energy screening and filtering device of claim 1 in whichsaid transparent plates form a portion of a roof in a buildingstructure.

22. The light energy screening and filtering device of claim 1 in whichsaid transparent plates form a canopy in an airplane.

23. The hermetically sealed air-free device of claim 18 in which saidtransparent plates are positioned horizontally.

k i t i i

2. The light energy screening and filtering device of claim 1 in whichsaid pump is in the low gravity point connection between said cavity andsaid reservoir.
 3. The light energy screening and filtering device ofclaim 1 in which said pump is in the high gravity point connectionbetween said cavity and said reservoir.
 4. The light energy screeningand filtering device of claim 1 in which a filter is positioned in atleast one of the connections between said cavity and reservoir to cleansaid liquids.
 5. The light energy screening and filtering device ofclaim 1 in which a bleeder valve is positioned in the system toeliminate air within the liquids.
 6. The light energy screening andfiltering device of claim 1 in which said reservoir has an expansionmeans for accommodating expansion and contraction of said liquids. 7.The light energy screening and filtering device of claim 6 in which saidexpansion means is a diaphragm in the side of said reservoir.
 8. Thelight energy screening and filtering device of claim 6 in which saidexpansion means is a rubber ball covered with coarse mesh wire.
 9. Thelight energy screening and filtering device of claim 1 in which saidimmiscible liquids are oils of different specific gravities.
 10. Thelight energy screening and filtering device of claim 1 in which saidimmiscible liquids are of different colors.
 11. The light energyscreening and filtering device of claim 1 in which one oil is a lightmineral oil and the other is a heavy glycol.
 12. The light energyscreening and filtering device of claim 1 in which two interphases arebetween the liquids in the system, one interphase rising as the otherinterphase descends as one liquid replaces the other in said cavity. 13.The light energy screening and filtering device of claim 1 in which saidcavity is defined by two transparent curved plates spaced apart by atubular gasket around the edge of the two plates.
 14. The light energyscreening and filtering device of claim 13 in which the plates areplastic.
 15. The light energy screening and filtering device of claim 13in which the plates are glass.
 16. The light energy screening andfiltering device of claim 1 in which a plurality of reservoirs is usedeach having a pump controlling it and a different liquid in eachreservoir for providing a different filtering and screening effect toserve as one of the liquids in the system, and a common liquid for theother liquid in the system, whereby the operation of any one pump whenthe common liquid is in the cavity causes the particular liquid in theoperated reservoir to fill the cavity.
 17. The light energy screeningand filtering device of claim 1 in which said transparent plates arepositioned horizontally.
 18. An hermetically sealed air-free device forscreening and filtering light radiation comprising two spacedtransparent plates having a gasket between them and positioned neartheir edges to define a sealed cavity therebetween; openings through oneof said plates at the upper and lower gravity points of said cavity; areservoir having upper and lower gravity point openings; a first conduitconnecting the upper gravity point opening in said reservoir with theupper gravity point opening in said cavity and a second conduitconnecting the lower gravity point opening in said reservoir with thelower gravity point opening in said cavity; two immiscible liquids ofdifferent specific gravities and of different light filtering propertiescompletely filling said device and having at least two separateinterphases between them within said device, said device beingcompletely free of air; and a reversible pump positioned in said secondconduit for pumping only the liquid of higher specific gravity to effecta movement of both liquids in or out of said cavity and in or out ofsaid reservoir.
 19. The light energy screening and filtering device ofclaim 1 in which said transparent plates form a substantial portion ofan automobile roof.
 20. The light energy screening and filtering deviceof claim 1 in which said transparent plates form a window in a buildingstructure.
 21. The light energy screening and filtering device of claim1 in which said transparent plates form a portion of a roof in abuilding structure.
 22. The light energy screening and filtering deviceof claim 1 in which said transparent plates form a canopy in anairplane.
 23. The hermetically sealed air-free device of claim 18 inwhich said transparent plates are positioned horizontally.